A rocker arm assembly for use in internal combustion engines comprising a rocker arm member having a longitudinal extent and including bearing means for mounting the member for oscillation about an axis perpendicular to its longitudinal extent. An insert body defining a push rod seat recess is press fitted in an end of the rocker arm member to extend transversely to the axis of oscillation. The insert has a first generally cylindrical end portion of a first diameter and a second axially aligned generally cylindrical end portion of a smaller diameter. The first end portion is spaced from the second end portion by an intermediate transition surface which is inclined relative to the axis of the cylindrical end portions. The push rod seat recess extends axially into the first end of the body. The relationship of the insert end portions and the transition surface prevents loosening of the insert in the rocker arm body.